Qt tip: Watch for deletion

If you have a QObject class that can be deleted at any time but you keep a pointer to it somewhere to work with it – you better watch it.

Deleting a class is perfectly fine. Deleting it and having to remember to set its pointer to ‘nullptr’ is critical, you might forget to. The best solution is to use QPointer to store your QObject class. A QPointer automatically sets itself to nullptr if the contained class has been deleted.

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How I put 245gb on a 47gb partition !

47G device 90% used, file on it is 245G
47G device 90% used, file on it is 245G (This VM was initially purposed for testing zfs 🙂

Yes, this is real.
No, there is a catch.

I was playing around with btrfs, a very modern and powerful filesystem for Linux, as I consider using it in the future with RAID5 (yes this is dangerous and maybe there is a blog post coming about this issue).

While trying to test btrfs’ abilities I was also testing the glorious super fast and effective zstandard (zstd) compression library by Facebook – for file system compression with btrfs. Zstd is relatively new to btrfs since Linux 4.14.

Curious about how I could make an easy and exciting test I decided to create a file with only zeroes with undefined file size.

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Access Samba Network Share with Windows 3.11

Windows 3.11 connecting to Samba on Ubuntu 18.04
Windows 3.11 connecting to Samba on Ubuntu 18.04

New versions of Samba have the authentification method “lanman” aka. LanManager of Windows 3.11 deactivated by default, increasing samba’s overall security. As lanman uses weak hashes for authentification user passwords can be bruteforced quickly.

Sadly this prevents Windows 3.11 from connection to your Samba shares.  But there is an easy way to allow old clients to connect again, but don’t forget that supporting old things lead to old vulnerabilities.

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